This chapter is from the book

In this chapter, we describe the Nexus Framework in its entirety. As you will see, Nexus is a relatively small and simple extension of Scrum. As we like to say, “Scaled Scrum is still Scrum.” Scrum itself is quite simple, at least to understand. When scaling, this simplicity is a big advantage because complexity is the enemy of scaling. Nexus’ simplicity also makes it highly adaptable, as we will see in subsequent chapters.

What is Nexus?

Nexus is a framework that enables multiple Scrum Teams to collaboratively work from a single Product Backlog to deliver at least one “Done” Integrated Increment every Sprint. “Multiple” means, typically, three to nine Scrum teams. Why not two? Because two teams can generally coordinate between one another without additional structure. Why nine? Just as Scrum recommends limiting teams to no more than nine members to improve cohesion and reduce complexity, Nexus recommends the same for the number of teams. Just as in Scrum, however, this upper limit is not absolute and slightly larger numbers may still work, depending on the circumstances. With Nexus we have discovered that collaboration complexity and coordination between teams increases significantly beyond nine teams, and for those cases some different techniques apply.1

Since Nexus builds on Scrum, its parts will be familiar to those who have used Scrum. The difference is that more attention is paid to dependencies and communication between Scrum Teams (see Figure 2-1).